Out of all of the people here that are asking for swimming, I wonder how many have tried it with only a Battle Dress Uniform (BDU, the standard U.S. camo outfit) coat (i.e., long-sleeved shirt with pockets) and trousers (i.e., pants)...
It'll kick your ass. I'd hate to have to try it with a Kevlar, L.B.E., loading magazines, a weapon, a full canteen, and boots on, not to mention a flak jacket or kevlar vest and loaded rucksack!
Swimming should definitely be left to civilian characters, Black Ops, combat divers, and frogs. Regular soldiers should only be able to wade or ford through the water (weapon raised over the head?) in a very light current, otherwise they'll need to drop most of their gear.
Comments from others who have been through "Water Indoctrination"?